STANFORD GROUP COMPANY INITIATES COVERAGE ON CALLISTO PHARMACEUTICALS WITH BUY RATING

NEW YORK, NY – April 22, 2005 – Callisto Pharmaceuticals, Inc. (AMEX: KAL), a biopharmaceutical company primarily focused on the development of drugs to treat cancer, today announced that the Stanford Group Company has initiated coverage on the company, with a BUY rating and a 12-month price target of $5.

Stanford Group is a full-service financial planning and investment management firm serving private investors, corporations, governments and institutions worldwide. To request a copy of the full report, please contact Aaron S. Reames, Senior Vice President of Equity Research for Stanford Group Company, at telephone 561-672-4716.

The information in the Stanford-Callisto report is provided for general information purposes only and should not be considered an individualized recommendation. All investors are encouraged to use multiple sources of investment information and to actively monitor their holdings. Callisto Pharmaceuticals or the industry sector discussed may not be a suitable investment for everyone. The report is based on information from a variety of sources and the statistical data is believed to be reliable but in no way are warranted as to accuracy, timeliness, completeness or reliability.

The report and rating are the final opinion of Stanford Group Company, and does not guarantee that any target price will be met or that the predicted business results will occur. Any and all revenue and earnings estimates and projections assume certain conditions and industry developments, which are subject to change and no guarantee is made as to the suitability or potential value of any investment.

The report is published for informational purposes only and is not to be construed as a solicitation or an offer to buy or sell any security. Opinions expressed are subject to change without notice and Stanford Group Company does not undertake to advise the public, nor is Stanford Group Company under any obligation to advise the public as to any changes in its projections or views of the industry or Callisto Pharmaceuticals. Past information is no guarantee or indication of future results. There is no existing relationship, investment banking or otherwise, between Callisto and the Stanford Group. The Stanford Group currently does not own any shares of the company’s stock. All disclosures can be found in the Important Disclosures section of the report.

About Stanford Group Company
Stanford Group Company is a full-service financial planning and investment management firm serving private investors, corporations, governments and institutions worldwide. Headquartered in Houston, the company currently has branch offices in Baton Rouge, Boca Raton, Boston, Denver, Dallas/Ft. Worth, Miami, Memphis, New York, and San Diego, with plans for additional offices.

Stanford Group Company offers a strategic, planning-based approach to wealth management, a process custom-tailored to the requirements of each client. Sophisticated technologies support high levels of personalized service and communications applications. With a full spectrum of nonproprietary products, the company’s financial consultants act as unbiased advisors, implementing sound investment strategies for their clients.

Stanford Group Company engages Bear, Stearns Securities Corp. for clearing services and custodianship of client assets. Bear, Stearns Securities Corp. is a wholly owned and guaranteed subsidiary of Bear, Stearns & Co. Inc., a leading international banking and securities firm. The relationship, along with Stanford’s network of professional advisors and analytical capabilities, forms the base from which Stanford Group Company provides stability, strength and protection of client assets.


About Callisto Pharmaceuticals, Inc.

Callisto is a biopharmaceutical company focused on the development of drugs to treat cancer and osteolytic bone disease. Callisto has two lead drugs in clinical development, Annamycin to treat relapsed leukemia, and Atiprimod to treat relapsed multiple myeloma. Callisto intends to initiate a Phase IIb clinical trial of Annamycin in relapsed acute lymphoblastic leukemia patients in mid 2005. Annamycin, a drug from the anthracycline family, has a novel therapeutic profile, including activity against resistant diseases and significantly reduced cardiotoxicity. Callisto’s second drug, Atiprimod, is in a Phase I/IIa clinical trial in relapsed multiple myeloma patients, and is a small-molecule, orally available drug with antiproliferative and antiangiogenic activity. Callisto also has drugs in preclinical development for melanoma, gastrointestinal inflammation, and a program focused on the development of a drug to protect against staphylococcus and streptococcus biowarfare agents. Callisto has exclusive worldwide licenses from AnorMED Inc. and M.D. Anderson Cancer Center to develop, manufacture, use and sell Atiprimod and Annamycin, respectively. For additional information, visit www.callistopharma.com.


Forward-Looking Statements

Certain statements made in this press release are forward-looking. Such statements are indicated by words such as "expect," "should," "anticipate" and similar words indicating uncertainty in facts and figures. Although Callisto believes that the expectations reflected in such forward-looking statements are reasonable, it can give no assurance that such expectations reflected in such forward-looking statements will prove to be correct. As discussed in the Callisto Pharmaceuticals Annual Report on Form 10-KSB for the year ended December 31, 2004,and other periodic reports, as filed with the Securities and Exchange Commission, actual results could differ materially from those projected in the forward-looking statements as a result of the following factors, among others: uncertainties associated with product development, the risk that products that appeared promising in early clinical trials do not demonstrate efficacy in larger-scale clinical trials, the risk that Callisto will not obtain approval to market its products, the risks associated with dependence upon key personnel and the need for additional financing.

For More Information:

Investor Relations:
Marty Tullio or Mark Tullio
McCloud Communications, LLC
949.553.9748
marty@McCloudCommunications.com
mark@McCloudCommunications.com

Company Contact:
Dan D’Agostino
Callisto Pharmaceuticals, Inc.
212.297.0010 x227
dagostino@callistopharma.com


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